Speed and tension control for yarn winder

ABSTRACT

The speed control includes a tension sensing element which is positioned in advance of the wind-up package to detect variations in tension of the yarn as it approaches the package. The rotational speed of the wind-up package is varied in response to a variation in tension in the yarn to thereby maintain uniform linear speed in the yarn being wound onto the wind-up package. A drive roll is positioned beneath and rotates the wind-up package by surface contact with the yarn and the wind-up package is normally maintained against the drive roll with a predetermined driving force and the control means operates to reduce the pressure and the driving point of the wind-up package against the drive roll and thereby decrease the rotational speed of the windup package in response to any increase in tension in the yarn approaching the wind-up package.

United States Patent [1 1 Hoffsommer et al.

[ SPEED AND TENSION CONTROL FOR YARN WINDER [75] inventors: Walter A.l-loflsommer, Ridley, Pa.;

Wieslaw J. Bartnicki, New Castle, Del.

[73] Assignee: Enterprise Machine and Development Corporation, NewCastle, Del.

[22] Filed: June 14, 1972 [2]] Appl. No.: 262,655

FOREIGN PATENTS OR APPLICATIONS 1,923,847 11/1969 Germany 242/45 PrimaryExaminer--Stanley N. Gilreath I Attorney-Paul B. Bell 7] ABSTRACT Thespeed control includes a tension sensing element which is positioned inadvance of the wind-up package to detect variations in tension of theyarn as "it approaches the package. The rotational speed of the wind-uppackage is varied in response to a variation in tension in the yarn tothereby maintain uniform linear speed in the yarn being wound onto thewind up package. A drive roll is positioned beneath and rotates thewind-up package by surface contact with the yarn and the wind-up packageis normally maintained against the drive roll with a predetermineddriving force and the control means operates to reduce the pressure andthe driving point of the wind-up package against the drive roll andthereby decrease the rotational speed of the wind-up package in responseto any increase in tension in the yarn approaching the wind-up package.

7 Claims, 3 Drawing Figures Patented July 3, 1973 3,743,202

WEssuRE- pomzce SPEED AND TENSION CONTROL FOR YARN WINDER This inventionrelates generally to speed and tension controls for yarn winders andmore particularly to a speed and tension control for the wind-up ortake-up package of a yarn texturing machine to maintain uniform linearspeed and tension in the textured yarn as it is being wound onto thetake-up package.

In various types of winders, it is desirable to wind the yarn onto thetake-up package under uniform conditions of speed and tension. This isparticularly critical in the winding of textured yarn since the bulkycharacteristics of the textured yarn are affected by a variation intension in the yarn. If uniform tension is not maintained in the take-uppackages, from one yarn texturing position to another and from onemachine to another, variations in the bulky characteristics of the yarnwill be imparted to the yarn and these variations will be apparent inany fabric woven or knitted of this yarn.

In the formation of take-up packages on surface driven winders, thepressure with which the take-up package engages the drive roll graduallyincreases as the size of the take-up package increases and this tends toincrease the speed at which the package is rotated, thereby graduallyincreasing the tension in the yarn from the beginning of the package toits full size. Also, in winding cone-shaped take-up packages, theaverage circumference of opposite ends of the cone do not remainconstant as the yarn builds on the cone so that there is a slightlydifferent surface speed at every point along the cone from one end tothe other. Thus, there is only one point at which there is a positivefrictional contact and this is usually referred to as the driving pointand shippage occurs at every other point along the line of contact. As acone-shaped take-up package is wound, there is usually a gradual changein the angle of the cone with a corresponding change in the location ofthe driving point so that the winding speed of the yarn is variedthroughout the winding of the package and the degree of bulkiness of theyarn correspondingly varies as it is wound onto the package undervarious rates of speed and at different degrees of tension.

Winders have been provided with counterweight devices in an attempt toovercome the problem of the increasing weight of .the take-up package.Winders have also been provided with a take-up package support whichincludes cam means to change the angle of the take-up package on thedrive roll as the package increases in size. However, these featuresstill do not completely solve the problem of tension variation in theyarn as the package increases in size.

With the foregoing in mind, it is an object of the present invention toprovide a speed and tension control for yarn winders which includes asensor positioned in advance of the take-up package for detectingvariations in tension of the yarn and for activating the control meansto vary the take-up speed of the package and thereby maintainuniformlinear speed and tension in the yarn as it is being wound onto thetake-up package.

In accordance with the present invention, the sensor of the presentspeed control is in the form of a lever having a flexible outer endportion and a pulley engaged by a loop of the yarn as it travels towardthe takeup package. The other end of the control lever operates an airvalve to permit air under pressure to be passed to an air cylinder forlifting some of the weight of the take-up package from the drive rolland to thereby slow the rate at which the yarn is wound onto the take-uppackage, thereby lengthening the yarn loop and reducing the tension inthe yarn. The drive roll is rotated at a rate which is normally higherthan the rate at which the yarn is textured so that the rotational rateof the take-up package may be slowed by the required amount by means ofthe present control so that the wind-up speed of the yarn is uniformlymaintained.

Other objects and advantages of the invention will appear as thedescription proceeds when taken in connection with the accompanyingdrawings, in which FIG. 1 is a somewhat schematic isometric view of onestation of an air jet texturing apparatus and illustrating the presentspeed control operatively associated therewith;

FIG. 2 is a somewhat schematic vertical sectional view through the upperportion of 'the apparatus illustrated in FIG. 1 and showing the mannerin which the sensor is operated by the yarn loop to reduce the weight ofthe take-up package on the drive roll, when necessary; and

FIG. 3 is an enlarged fragmentary side elevational view of the portionof the sensor lever which operates the air valve.

The speed and tension control of the present invention is illustrated inFIG. 1 as being associated with the winder of an air jet texturingapparatus. However, it is to be understood that the present speed andtension control may be used with other types of yarn winding apparatusand other types of yarn texturing machines. As shown in FIG. 1, the yarnY is withdrawn from a suitable yarn supply source in the form of a yarnpackage 10. The yarn is drawn through a suitable tension device, such asa tension fork I1, and is then wound around first yarn feed roll means,in the form of a positive feed roll 12.

The yarn Y then enters a fluid bulking jet l3 and passes around secondyarn feed roll means, in the form of a positive feed roll 14. The yarnis looped and engaged by the sensor means of the present invention, in amanner to be presently described. The yarn then passes beneath a fixedguide pulley 15, over an oil conditioning roller 16, over a bale 17,through a yarn traversing guide 18 and is then wound onto a wind-up ortake-up package 20. The take-up'package 20 is supported at one end forrotation in the lower end of an arm 21 of a pivoted support bracket 21awhich is pivotally supported adjacent its rear end on a pivot shaft 22.I

A control pin 21b extends rearwardly from the lower end of the arm 21and rides on a cam 21c, fixed on the shaft 22. The cam 21c changes theangular position of the take-up package 20 as it increases in size.

Counterweight means is provided to counter the increase in weight ofthe. take-up package as it increases in size. The counterweight meansincludes an upstanding lever 23 fixed at its lower end to the supportbracket 21a and having a counterweight shaft 24 at its upper end. Oneend of a flexible band 25 is connected to the support bracket 21a andextends upwardly and over the shaft 24. The band 25 then extendsdownwardly with its lower end suitably supporting counterweight 27. Thetake-up package 20 normally rests by gravity, subject to the action ofthe counterweights 27, on a cone drive roll 30 which is normally drivenat the same speed as the speed at which the yarn is textured, i.e., thespeed at which the yarn is withdrawn from the jet 13 by the positivefeed roll 14.-

in accordance with the present invention, the drive roll 30 is driven ata slightly faster speed than the yarn is withdrawn from the jet 13 bythe feed roll 14 and sensor means is positioned between the second feedroll 14 and the take-up package 20 and is engaged by a loop of thecontinuously moving yarn. The sensor means is movable in response to anyincrease in tension and linear speed of the yarn traveling between thesecond feed roll 14 and the take-up package 20 and operates to reducethe speed of the take-up package and to maintain the wound yarn underuniform tension. The sensor means includes an idler pulley 31 which isrotatably supported on the free end of an outer leaf spring end portion32 of a sensor control lever 33. The sensor lever 33 is supported forlongitudinal adjustment adjacent its opposite end in a bracket 34 (FIG.3) and held in adjusted position by a set screw 35. The bracket 34is'pivotally supported on upstanding arms 36 of switch means in the formof a miniature air valve 37 which forms a part of the operator means forreducing the weight of the take-up package 20 against the drive roll 30to thereby change the driving point and to decrease the driving forceapplied to the take-up package 20 by the drive roll 30 and to therebyreduce the rotational speed of the take-up package 20 and to maintainuniform linear speed and tension in the yarn being wound on the take-uppackage.

in the present instance, the operator means is illustrated as includingan air cylinder 40 which is supported in a plate 40a which is pivotallysupported inter mediate the ends of a bracket 42. The lower end of thebracket 42 is fixed on the shaft 22 and the upper end supports theminiature air valve 37. The air cylinder 40 is provided with a piston 41which extends outwardly therefrom and its free end is suitably connectedto the counterweight shaft 24. An air pressure supply line 43 isconnected at one end to the air valve 37 and at its other end to the aircylinder 40. An air pressure supply line 44 is connected at one end to asuitable source of air under pressure, as indicated at 45, and its otherend is suitably connected to the air valve 37. The air valve 37 isnormally closed and when the yarn loop is shortened, because the yarn isbeing wound onto the take-up package 20 at a speed which is in excess ofthe speed of the second positive feed drive roll 14, the free outer endof the lever 33 is lowered to thereby open the air valve 37. Air thenenters the air cylinder 40 and moves the piston rod 41 outwardly to movethe lever 23 in a clockwise direction and thereby reduce the pressure ofthe take-up package 20 against the drive roll 30. Thisdecreases thedriving force applied to the take-up package andreduces the speed atwhich the yarn is wound onto. the take-up package so that the yarn loopwill again lengthen and the sensor lever 33 will raise upwardly, closingthe air valve 37. A bleed port adjustment screw 37a (FIG. 3) may beprovided in the valve 37 to regulate the speed of return of the piston41.

In the drawings and specification, there has been set forth a preferredembodiment of the invention, and although specific terms are employed,they are used in a generic and descriptive sense only and not forpurposes of limitation.

That which is claimed is:

1. in an apparatus for texturing yarn and for winding the textured yarnonto a take-up package at a substantially constant predetermined linearspeed and under substantially constant tension conditions, saidapparatus including a yarn supply source, a fluid bulking jet spacedfrom said yarn supply source, first yarn feed roll means positionedbetween said yarn supply and said jet for feeding yarn into said jet ata given rate, second yarn feed roll means for withdrawing the yarn fromsaid jet at a predetermined lesser rate than said given rate, yarntraversing means for feeding the-yam to and fro across said take-uppackage, a drive roll positioned beneath and rotating said take-uppackage by surface contact with the yarn wound thereon, and meansrotatably supporting said take-up package against said drive roll with agiven pressure whereby the yarn wound on said take-up package isnormally maintained against said drive roll with a predetermined drivingforce, the combination therewith of a. sensor means positioned betweensaid second yarn feed roll means and said take-up package and beingengaged by the continuously moving yarn, said sen-- sor means beingmovable in response to any increase in tension and linear speed of theyarn between said second yarn feed roll means and said take-up package,and

b. operator means operable in response to movement of said sensor meansfor reducing said given pressure of said take-up package against saiddrive roll to thereby decrease the drivingforce applied to said take-uppackage by said drive roll and to reduce the rotational speed of saidtake-up package and to maintain uniform linear speed in the yarn beingwound onto said take-up package.

2. in an apparatus according to claim 1 wherein said take-up packagesupport means includes counterweight means for maintaining saidpredetermined driving force normally applied against said drive roll bythe weight of said take-up package, and wherein said operator means (b)is engageable with said counterweight means for reducing saidpredetermined driving force normally applied against said drive roll bysaid take-up package.

3. In an apparatus according to claim 1 wherein said sensor means (a)includes a control lever pivotally supported adjacent one end, a yarnguide pulley at the other end of said control lever and over which theyarn passes; and wherein said operator means (b)- includes switch meansoperable by said control lever.

4. In an apparatus according to claim 3 wherein said operator means (b)includes a pneumatic cylinder operatively connected to saidcounterweight means and being operable by said switch means to decreasesaid predetermineddriving forcenormally against said drive roll by saidtake-up package. 1 f- 5. In an apparatus according to claimf4-whereinsaid switch means comprises an air valve for selectively permitting airunder pressure to enter said pneumatic cylinder in response to movementof said control lever.

6. in a machine for winding yarn at a substantially constantpredetermined linear speed and under sub stantially constant tensionconditions, said winding machine including a yarn supply source, afreely rotatable take-up package onto which the yarn is wound, yarntraversing means for feeding the yarn to and fro across said take-uppackage, a drive roll positioned beneath and rotating said take-uppackage by surface contact with the yarn wound thereon, and meanssupporting said take-up package against said drive roll with a givenpressure whereby the yarn wound on said take-up package is normallymaintained against said drive roll package by said drive roll and tothereby reduce the rotational speed of said take-up package and tomaintain uniform tension and linear speed in the yarn being wound ontosaid take-up package.

7. In an apparatus according to claim 6 wherein said take-up package isconical and is normally maintained in contact with said drive roll bythe weight of said take-up package and by counterweight means, andwherein said operator means is operatively connected to saidcounterweight means.

1. In an apparatus for texturing yarn and for winding the textured yarn onto a take-up package at a substantially constant predetermined linear speed and under substantially constant tension conditions, said apparatus including a yarn supply source, a fluId bulking jet spaced from said yarn supply source, first yarn feed roll means positioned between said yarn supply and said jet for feeding yarn into said jet at a given rate, second yarn feed roll means for withdrawing the yarn from said jet at a predetermined lesser rate than said given rate, yarn traversing means for feeding the yarn to and fro across said take-up package, a drive roll positioned beneath and rotating said take-up package by surface contact with the yarn wound thereon, and means rotatably supporting said take-up package against said drive roll with a given pressure whereby the yarn wound on said take-up package is normally maintained against said drive roll with a predetermined driving force, the combination therewith of a. sensor means positioned between said second yarn feed roll means and said take-up package and being engaged by the continuously moving yarn, said sensor means being movable in response to any increase in tension and linear speed of the yarn between said second yarn feed roll means and said take-up package, and b. operator means operable in response to movement of said sensor means for reducing said given pressure of said take-up package against said drive roll to thereby decrease the driving force applied to said take-up package by said drive roll and to reduce the rotational speed of said take-up package and to maintain uniform linear speed in the yarn being wound onto said take-up package.
 2. In an apparatus according to claim 1 wherein said take-up package support means includes counterweight means for maintaining said predetermined driving force normally applied against said drive roll by the weight of said take-up package, and wherein said operator means (b) is engageable with said counterweight means for reducing said predetermined driving force normally applied against said drive roll by said take-up package.
 3. In an apparatus according to claim 1 wherein said sensor means (a) includes a control lever pivotally supported adjacent one end, a yarn guide pulley at the other end of said control lever and over which the yarn passes; and wherein said operator means (b) includes switch means operable by said control lever.
 4. In an apparatus according to claim 3 wherein said operator means (b) includes a pneumatic cylinder operatively connected to said counterweight means and being operable by said switch means to decrease said predetermined driving force normally against said drive roll by said take-up package.
 5. In an apparatus according to claim 4 wherein said switch means comprises an air valve for selectively permitting air under pressure to enter said pneumatic cylinder in response to movement of said control lever.
 6. In a machine for winding yarn at a substantially constant predetermined linear speed and under substantially constant tension conditions, said winding machine including a yarn supply source, a freely rotatable take-up package onto which the yarn is wound, yarn traversing means for feeding the yarn to and fro across said take-up package, a drive roll positioned beneath and rotating said take-up package by surface contact with the yarn wound thereon, and means supporting said take-up package against said drive roll with a given pressure whereby the yarn wound on said take-up package is normally maintained against said drive roll with a predetermined driving force, the combination therewith of a. sensor means positioned in advance of said take-up package and engaged by the continuously moving yarn, said sensor means being movable in response to any increase in tension and linear speed of the yarn moving toward said take-up package, and b. operator means operable in response to movement of said sensor means for reducing pressure of said take-up package against said drive roll to thereby reduce the driving force applied to said take-up package by said drive roll and to thereby reduce the rotational speed of said take-up package and to maintain uniform tension and linear speed in the yArn being wound onto said take-up package.
 7. In an apparatus according to claim 6 wherein said take-up package is conical and is normally maintained in contact with said drive roll by the weight of said take-up package and by counterweight means, and wherein said operator means is operatively connected to said counterweight means. 